1. Field of the Invention
The present invention relates generally to air conditioners having a humidifying function, and more particularly, to an air conditioner having a humidifying function without the necessity of water supply for humidification.
2. Description of the Related Art
There have been air conditioners having a humidifying function without the necessity of water supply for humidification. Such an air conditioner employs a material having necessary hygroscopicity and gas permeability (hereinafter referred to as absorbent) for humidification. During humidification, moisture in the air is absorbed into an absorbent, then air warmed by a heater passes through the absorbent, and therefore the moisture desorbed from the absorbent is absorbed by the warmed air, which is supplied indoors as humidified air.
As such an air conditioner capable of humidifying air without the necessity of water supply, for example, Japanese Patent Laying-Open No. 63-286634 discloses a humidifier which takes in moisture from outdoor air and humidifies indoor air. FIG. 27 is a view showing the structure of the humidifier disclosed by Japanese Patent Laying-Open No. 63-286634. In the humidifier, outdoor air coming in from the inlet of a tube for passing outdoor air through the humidifier passes through and has its moisture absorbed by a solid absorbent 131 rotating around the axis of the tube, and is let outdoors from an outlet as dried air. Indoor air coming in from an inlet of a tube for passing indoor air through the humidifier is heated by a heater 132, absorbs moisture disorbed from solid absorbent 131 to be highly humid air as it passes therethrough, and is sent indoors as humidified air from the outlet. Note that solid absorbent 131 is driven to rotate by a driving motor 133.
As described above, in the humidifier shown in FIG. 27, outdoor and indoor air is taken into the humidifier, through separated and independent air flow passages, which impedes miniaturization of the device. Furthermore, if the humidifier is apart from the outdoors, there is a great loss in pressure by sending air for the purpose of suction/exhaustion of air from/to the outdoors, resulting in increase in the size and noise level of a blower member. There is known a conventional air conditioner which includes a ventilation duct connecting an outdoor unit and an indoor unit for the purpose of ventilation, dehumidification, and humidification without water supply as described above. FIGS. 28A and 28B show the configuration of the indoor unit of such a conventional air conditioner. FIGS. 28A and 28B show the indoor unit 121 of the air conditioner and a ventilation duct 122 letting in outdoor air into indoor unit 121. Note that when indoor unit 121 is installed, the ventilation duct, a refrigerant pipe, a drain pipe, and a power line pass through a side surface of indoor unit 121 as shown in FIG. 28A or via the upper or lower surface of outdoor unit 121, then through a through hole formed on a wall and connected to the outdoor unit which is not shown. FIGS. 29A-29D show in enlarged form the vicinity of ventilation duct 122 in FIGS. 28A and 28B. In FIG. 29A, in the vicinity of ventilation duct 122, there are provided a refrigerant pipe 125, a drain hose 126 to discharge outdoor drainage generated by a heat exchanger (not shown) in an indoors unit 121 shown in FIGS. 28A and 28B, and a power line 127 to supply electric power to the outdoor unit from the indoor unit 121.
When the indoor unit 121 is installed, an extension refrigerant pipe is usually used on the side of indoor unit 121, and the connecting portion of the refrigerant pipe on the side of outdoor unit and the extension refrigerant pipe is provided on the side of the indoor unit 121. The structure of the connecting portion is shown in FIGS. 29B and 29C. As shown, nuts are used for a connecting portion 124 connecting refrigerant pipe 125a on the outdoor unit side and refrigerant pipe 125b for extension, and the diameter of connecting portion 124 is larger than the diameter of refrigerant pipe 125 (125a, 125b). Connecting portion 124 is provided in the vicinity of ventilation duct 122 at a position opposite to ventilation duct 122. Refrigerant pipe 125 and connecting portion 124 have their surfaces wound with a heat insulating tape or covered with a cover for the indoor unit.
Note that as shown in FIG. 29D, some air conditioners have a ventilation duct 122, a refrigerant pipe 125, a drain pipe 126 and a power line 127 formed and accommodated integrally inside a pipe 123. In such a case, as is the above device, the connecting portion 124 of refrigerant pipe 125 has a large diameter and is positioned near ventilation duct 122.
As in the air conditioners shown in FIGS. 28A and 28B and 29A-29D, when a heat insulating tape is wound around refrigerant pipe 125 and connecting portion 124, stress is imposed on ventilation duct 122 which is near and opposite to connecting portion 124, and ventilation duct 122 is prone to damages. In order to avoid the damages, a space is secured between ventilation duct 122 and refrigerant pipe 125 for the expanded diameter of connecting portion 124 corresponding to the width of the nuts, and connecting portion 124 and ventilation duct 122 are kept from contact. Thus, a large dead space forms.
A conventional air conditioner capable of ventilation is disclosed by Japanese Patent Laying-Open No. 4-73531. FIG. 30 is a cross sectional view showing in the vicinity of the ventilation path of the disclosed air conditioner. FIGS. 31A and 31B are cross sectional views showing the ventilation path in FIG. 30. In FIG. 30, the air conditioner includes an indoor unit 114 on the indoor side of a wall 115 separating the indoor and outdoor. When indoor air is discharged outdoors from indoor unit 114, indoor air is taken into a duct 105 from indoor intake/exhaust opening 108 by the function of an outdoor blower 107, and is blown out from an outdoor intake/exhaust opening 109 through a sleeve 106. When outdoor air is taken indoors, outdoor air is taken into sleeve 106 from opening 109 by the function of blower 107, and blown out into the room from opening 108 through duct 105. Sleeve 106 is used to draw a refrigerant pipe 110, a drain hose 111, and a power line 116 from the indoors to the outdoors through wall 115, and there is a ventilation path 117 in sleeve 106.
Blower 107 for ventilation and duct 105 leading to the front side of indoor unit 114 communicate with sleeve 106 to form a ventilation path 117. A pipe bundle 112 including refrigerant pipe 110, drain hose 111 and power line 116 are integral in form in sleeve 106. A guide plate 113 is attached to pipe bundle 112 to secure ventilation path 117 in sleeve 106.
In such an air conditioner, refrigerant 110, drain hose 111 and power line 116 are bundled in sleeve 106 as pipe bundle 112, and the remaining space in sleeve 106 is used for ventilation path 117. Therefore, when refrigerant pipe 110, drain hose 111 and power line 116 are passed through a through hole for tubing provided in wall 115, sleeve 106 having the same diameter as the through hole cannot be easily inserted therethrough, and it takes much time to install the air conditioner as a result.
Conventionally, in order to accommodate and protect pipes such as a drain pipe for drainage water from the indoor unit of an air conditioner and a refrigerant pipe connecting the indoor and outdoor units, and an electric wire, tubing covers of resin or the like varied in shape and fashion are used. When the pipes and electrical wire passing through the through hole in the wall from the indoor unit are bent along the wall and attached to the outdoor unit, there is provided a corner tubing cover which connects to the linear shape tubing cover along the wall and the through hole and protects the bent portion of the pipes.
Such a corner tubing cover is disclosed by Japanese Patent Publication No. 62-48119. The disclosed cover connects to the through hole in the wall and another tubing cover along the wall surface to cover the expanded and bent portion of the pipes, and is separated into two portions for the ease of attachment.
Furthermore, Japanese Utility Model Laying-Open No. 63-52028 discloses a hood type weathertight cover which keeps wind and rain from coming into the room at the time of taking in/exhausting air. An indoor intake/exhaust fan is provided on the outdoor side of a duct to keep wind and rain from coming into the room, and the disclosed cover has an insect proof screen.
Furthermore, as disclosed by Japanese Patent Laying-Open No. 5-71753, there is provided a ventilation unit on the outdoor side of the through hole in the wall which is in cooperation with the air conditioner to allow a ventilation opening for distributing outdoor air, the inner space of a pipe for the through hole in the wall is partitioned into a path for the pipes and an intake/exhaust path for ventilation and an intake window is provided under the outdoor ventilation unit.
It is complicated to attach such a corner tubing cover for the bent portion of the pipes for difference in size between connecting portions when the use of another tubing cover having a different diameter along the wall is desired.
If the hood type weathertight cover is provided for the corner portion of the pipes, another opening for passing the tubing cover should be provided on a side surface of the weathertight cover in order to bend the pipes in any lateral orientation depending upon the condition of installing the outdoor unit.
Furthermore, simply providing an intake window under the ventilation unit cannot prevent wind, rain and insects from coming in through the opening.